On June 26, 2013, the U.S. Supreme Court issued a ruling nullifying parts of the Defense of Marriage Act (DOMA), the 1996 federal legislation that defined marriage, for federal purposes, as a union between one man and one woman. The court’s 5–4 decision in the case United States v. Windsor also invalidated DOMA’s definitional section and thus made federal benefits available to married same-sex couples. The Internal Revenue Service announced in late August that same-sex spouses would be treated the same as other married couples for federal tax purposes. This turn of events, less than a decade after Massachusetts became the first state to recognize such marriages in 2004, was clear evidence that the legal normalization of same-sex marriage may have had quicker success than any other social movement in American history. (See Special Report.) By 2010, the first year for which the U.S. Census Bureau identified married same-sex couple households, more than 130,000 such marriages existed in...